mod_dontdothat allows you to block update REPORT requests against
certain paths in the repository. It expects the paths in the REPORT
request to be absolute URLs. Serf based clients send relative URLs
instead of absolute URLs in many cases. As a result these clients
are not blocked as configured by mod_dontdothat (CVE-2013-4505).

When SVNAutoversioning is enabled via SVNAutoversioning on,
commits can be made by single HTTP requests such as MKCOL and PUT.
If Subversion is built with assertions enabled any such requests
that have non-canonical URLs, such as URLs with a trailing /, may
trigger an assert. An assert will cause the Apache process to abort
(CVE-2013-4558).
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